Evaluation of onchocerciasis using seroprevalence in some ivermectin treated Local Government Areas of Kaduna State, Nigeria

Abstract

Kachia and Kagarko LGAs are among the LGAs that have been treated with Ivermectin consistently for 19 years according to the records of Kaduna State Ministry of Health. Hence this study was carried out to conduct an appraisal of these selected areas in order to determine its efficacy, longevity and corroborate or otherwise the issue of recrudescence of the disease. A cross sectional study was conducted in May, 2018 to investigate the prevalence of onchocerciasis in Kachia and Kagarko LGAs of Kaduna State, Nigeria. A total number of 208 participants were screened using SD Bioline onchocerciasis IgG4 kit from the two LGAs, 23 (11.1%) were found to be positive for IgG4 antibodies to O. volvulus. Result of the Chi square analyzes showed that there were no significant association between sex and seroprevalence (X²=0.377, df=1, p=0.593), LGAs and seroprevalence (X²=1.119, df=1, p=0.290, CI=95%) however, a significant association between age and seroprevalence (X²=13.408, df=5, p=0.020) was recorded. Occupationally, the LGAs had a significant association (X²=14.420, df=4, p=0.006). In Kachia LGA, there was equally a significant association (X²=10.848, df=4, p=0.028) while, in Kagarko there was no significant association (X²=5.866, df =4, p=0.209) in the seroprevalence. Significant  association was equally recorded between seroprevalence and compliance to ivermectin in Kachia (X²=27.419, df=1, p=0.05) and Kagarko (X²=33.269, df=1, p=0.05). Conclusively, there was  reduction in Onchocerca infection due to adherence to ivermectin intake by the inhabitants. Therefore, regular surveillance of endemic areas is to be carried out promptly in order to ensure compliance to prescribed annual ivermectin dosage and identify and treat infected individuals